In recent years, with rapid development of the Internet and progress of data compression and transmission technologies, a multimedia communication technology has witnessed unprecedented development, and various multimedia applications are gradually integrated into people's life; NGOD (Next Generation On Demand) is a new-generation multimedia video on demand service architecture.
A basic NGOD architecture is made up of multiple components, including: a media server, an on-demand client, a back-end management device Backoffice, and an EPG (Electronic Programmer Guide, electronic programmer guide) server. The media server is responsible for sending a digital video stream to a terminal device through a transmission network and an edge device, and usually uses, within its fault-tolerant capability, a mass storage hard disk to store audio and video content in an MPEG (Moving Pictures Experts Group, Moving Pictures Experts Group) format. Particularly, the media server supports operations such as pausing, fast forwarding, and rewinding. The on-demand client is a device connected to a display device and an external signal source, and is responsible for converting compressed digital signals into audio and video signals. The back-end management device Backoffice is used for user authentication and resource management in an on-demand session. The EPG server is used to provide a program guide for users, where the program guide includes a live program guide, a forecast program guide, and a time-shifted program guide, and the program guide provides related information about various programs.
The NGOD architecture supports a program playback service. When a user watches a live program online, the user can press a playback button to enter a playback mode to watch a time-shifted program, and can perform operations such as fast forwarding and rewinding for the time-shifted program. At present, although switching between time-shifted programs can be implemented when a time-shifted program is watched in the playback mode, switching of the time-shifted program can be completed only after multiple signaling interactions between the on-demand client and the media server in the process of switching the time-shifted program. Therefore, a lot of signaling interactions and a long switching time are needed, and switching efficiency is low.